There's an issue with computing the bottom of the track text when the track text is drawn over the progress bar.
As you can see, when playing, 1px of the bottom text gets cut off and it's more pronounced when slim icon setting is enabled.
It's my Dark Green Bee skin, and Bee-liever's bee78 skin shows the exact same behavior.
I tried with v3.1 and it was the same, so obviously it's been always the case since it's supported.